Clutch



Jan. 29, 193 5.

E. F. DlCKIEso JR. 1,9 9 4. CLUTCH Filed 0ct. 2O, 1931 2 Sheets-Sheet l TTORNEY5 Jan. 29, 1935. E. F.- DICKIESION, JR

CLUTCH Filed Oct. 20, 1931 2 sheets-sheet? INVENTOR 1 ATTORNEYS Patented a... 29, 1935 1 39 4. 7

UNITED STATES PATENT OFFICE CLUTCH Edward F. Dickieson, Jr., Detroit, Mai... 8.8-.

Signor to Eaton Manufacturing Company, a corporation of Ohio 1 Application October 20, 1931, Serial ,No. 569,972 3 Claims. (01. 192-103) This invention relates to power transmitting automatically be disconnected from the road mechanisms and particularly to that type thereof wheels; to provide a clutch responsive .to certain commonly known as clutches and which are emconditions of torque reaction existing between ployed for the purpose of releasably connecting the engine and the road wheels to automatically 5 a driving and a driven member. Although apdisconnected the same; to provide a motor-ve- 5 plicable for use in connection with a variety of hicle driving mechanism in which reversal of the different types of mechanisms the invention is torque reactions in the connections between the particularly applicable for use in connection with road wheels and the engine, in one direction,

motor vehicles for the purpose of releasably conwill automatically release the clutch; to provide meeting the engine thereof with the road wheels a driving mechanism for motor vehicles by the 10 of the vehicle. use of which the transmission may be more easily Objects of the invention are to provide a clutch shifted; and to provide a clutch for an automotive of novel construction; to providea clutch which Vehicle automatically releasable under certain opwill disconnect the driving and driven elements erating conditions, together with manually operthereof under certain conditions of operation; able means efiective to prevent such automatic 15 to provide a. clutch embodying means' for autooperation. I matically disconnecting the driving and driven The above being among the Objects of the P 7 elements thereof when the speed of the driving ent invention the same consists in certain feaelement falls below a predetermined value; to tures of construction and combinations of parts provide a clutch in which provisions are incorto be hereinafter described with reference to the 20 porated for automatically disconnecting the drivaccompanying drawings, and then claimed, having and driven elements thereof under conditions ing the above and other objects in view; where the driven element tends to drive the driv- In the accompanying drawings which illustrate ing element; and to provide'a clutch embodying suitable embodiments of the present invention '25 both automatic and manual control means thereand in which like numerals refer to like parts throughout the several different views,-

Another object is to provide a clutch embody- Figure 1 is a fragmentary partially broken ing driving and driven elements together with side elevational view of a unitary power plant for centrifugally actuated means for controlling the a motor vehicle, and in which a suitable embodi- '30 engagement thereof; to provide a clutch of the ment of the present invention is shown incorpotype described in which the force of the centrifrated.

ugally actuated means is resiliently impressed Fig. 2 is an enlarged view. taken on the line 2--2 upon the clutch element; to provide a clutch of of Fig. 1, constituting a rear elevational view of the type described in which the force of centhe clutch embodied in the construction illustrifugally actuated members acting to maintain trated in Fig. 1. 35 the clutch in engaged position is transmitted to Fig. 3 is a partially broken vertical sectional the movable clutch element through resiliently View taken on the line 3-3 of Fig. 2. mounted members; to provide a clutch of the Fig. 4 is a vertical sectional view taken per- -type described in which such resilient members pendicular to the axis of the clutch as on the are subject to adjustment; to provide a cenline 4--4 of Fig. 3; I u 40' trifugal type of clutch in which means are pro- Fig. 5 is a perspective view of one of the cam vided. for automatically synchronizing the acmembers cooperating with the driven member of tion of the various centrifugally actuated memthe clutch shown in the preceding view. bers; and to provide a clutch including a plural- Fig. 6 is a view similar to Fig. 3 but showing ity of masses adapted to be acted upon by .cena modified form of my invention.

' trifugal force tending to maintain the clutch in Fig. I is a view taken substantially on the line engaged position, and in which means are pro- 77 of Fig; 6 and showing one of the clutch cam vided for synchronizing the movements of such elements in end elevation.

.weights whereby to maintain a condition of bal- Fig. 8 is an enlarged fragmentary sectional view ance in the clutch as a whole. taken on the line 8-.-8 of Fig. 7. 50

Other objects of the invention are to provide a Fig. 9 is a fragmentary enlarged sectional view clutch for connecting the engine and road wheels taken on the line 9-9 of Fig. '7; of a motor vehicle andso constructed that upon Fig. 10 is a perspective view of the clutch prescertain conditions of operation when the road sure ring element of the construction shown in wheels tend to drive the engine, the engine will Fig. 6.

tofore been proposed, in order to obtain the beneflt of the combined action of both of such clutches it has been necessary to provide two distinct and substantially independent clutch units, necessarily embodying considerable expense and, as far as I am aware, necessitating the employment of a structure of substantial bulk in comparison with clutch structures as employed .in present day motor vehicles. One of the main pur poses of the present invention is to provide a,

single clutch structure embodying advances of both a centrifugally actuated clutch and an overrunning clutch, and while such clutch mechanism is obviously adaptable for use in connecmotor vehicles, and co tion with a great variety of mechanisms, it is particularly-adaptable for use in connection with illustration principally its description and explanation will be confined to its adaptations of motor vehicle uses only, it being understood that its adaptation to other uses will be obvious from the description thereof.

Referring to the drawings it may be well to first, refer to Fig. 11 in which a motor vehicle ismore-or-less diagrammatically indicated as having a chassis frame 15, front wheels 16, rear wheels 17 and an engine 18. The front wheels 16 are connected to the chassis 15 by means of an axle (not shown) and spring 20 in a converstional manner. The rear wheels 17. are mounted upon a suitable driving axle 21 which may be of conventional construction and which in turn is connected by'springs such as 22 to the chassis frame 15 in a conventional manner. As also indicated in Fig. 1, a clutch 23 is ing 24 secured to the rear end of the engine 18, and mounted upon the rear end of the housing 24 is a transmission mechanism indicated generally at 25 and which may be of any conventional construction. A propeller shaft 26 op eratively connects the on 25 with the rear axle 21.

Referring now to Figs. 2 to 5 inclusive, and particularly to Fig. 3it will be noted that the rear end of the engine crank shaft 30 has secured thereto by bolts such as 31 in a conventional manner a flywheel 32 which, in accordance with conventional practice, forms apart of a clutch mechanism. 'In accordance with conventional practice the flywheel 32 may be pe-- ripherally' provided with a ring gear 33 for cooperation with an electric starter 34 in accordance with conventional practice. In accordance with the present invention the rear face of the flywheel '32- is provided with a plurality of pairs 5 of rearwardly projecting spaced ears or lugs 35 arranged thereonin a circle concentric with the shaft 30. Radially inwardly of the lugs 35 the flywheel 32 is provided with a flat rear face 36 disposed in a planepernle gdicular ;to the axis of the crank shaft 30. e rear end of the crank shaft 30 is centrally recessed as at 40 and receivestherein a bearing bushing .41- which rotatably supports the forward axis of the. crank end of the clutch driven shaft 42.- 75' T A radially flanged sleeve 44 is rotatably mountsuch clutch as have here-- uently, as-a matter of enclosed in a housand the shaft ed upon the shaft 42 immediately rearwardly of the flywheel 32 and has secured thereto by bolts such as 45 a clutch driven plate 46 which may be provided with the .usual annular friction facings 47 on opposite sides thereof. The facing 47 on the forward side of the disc 46 normally lies in substantially contacting relationship with respect to the rear face 36 of the flywheel 32 in accordance with usual practice. Axial movement of the sleeve 44 on the shaft 42 is limited by reason of its being conflned between the rear end of the crankshaft 30 and a thrust member 50 secured against movement to the shaft 42.

As best illustrated in Fig. 5, the sleeve member 44 is provided with a tubular peripheral flange portion 52 the rearedge of which is machined to provide a plurality of ratchet-like teeth 53 presenting helical cam surfaces 54. The surfaces 54 are inclined axially rearwardly in the direction of rotation of the crankshaft 30 for apurpose that will hereinafter be explained. A flat surface 55, lying in a plane radial to the sleeve 44, is provided between each adjacent part of teeth 53.

The shaft 42 rearwardly of the sleeve 44 is splined as at 58 (see Fig. 3) and slidably received on and maintained against relative rotation on the shaft 42 by the splines 58 in a forwardly opening cup shaped member 59 of a diameter corresponding with the peripheral flange 52 on the sleeve 44. The forward edge of the member 59 is machined to a shape complementary to the shape of.the teeth 53 on themember 54 so that the teeth thereof may inter-engage with the teeth 53. a torsion spring so surrounding the shaft 42 between the sleeves 44 and the cup member 59 has opposite ends thereof anchored in the sleeve 44 and cup 59 respectively and is normally maintained under torsion tending to rotate the cup 59 in a right hand direction as viewed from theright of Fig. 3, and which direction of rotation tends to bring the faces '55 of the teeth on the member 44 and the corresponding faces of the teeth on the member 59 into contact with each other.

A pressure plate riphery adapted to interflt the lugs 35 on the flywheel 32 in order to maintain it against relative rotation with respect to and centrally of the flywheel 32 without restricting axial movement thereof, is positioned immediately rearwardly of the clutch disc 46 and, as in usual constructions, is adapted when properly actuated to clamp the clutch disc 46 against rotation to the rear face 36 of the flywheel 32.

Arms in a generally radial plane with respect .to the clutch are pivotally secured by means of pins such as 71 between each pair of ears 35 on .the flywheel 32. -Each of-the arms 70 has rigidly associated therewith a forwardly extending weight portion 72, the rear face of the flywheel 32 being recessed as at 73 for the free reception of the forward end of the weight 72 therein. Stop pins 75 32 at the bottom of each of the recesses 73 pro-. jects into the path of movement of the respective .weights 72 in order to limit their outward movement therein. I Each of'the arms 70 between its pivot pin 71 42 is provided with a forwardly opening bore 78 allel to the axis of the shaft 42, and within each of the bores 78 is-received a plunger 79 having a stem -80 which slidably projects through the arm 70 at 1 the rear end of the bore 78 and on such projecting having a notched out pe-.

whose axis is approximately par-v secured in the flywheel end threadably receives a nut 81. A coil spring 82 encircles each of the stems 80 within the bore '78 and is maintained under constant compression between the ends of the bore- '78 and the'plunger the'corresponding face of the arm '70 and into a position which, under normal 1 conditions when the clutch is not rotating, is slightly spaced from the pressure plate 65. y

The radially inner ends of the arms '70 extend inwardly and rearwardly into spaced relation with respect to the surface of the shaft 42 where they are reduced in size to form fingers 85 and all these fingers 85 are slidably received within the annular groove 86 of the axially slidable collar 87 relatively non-rotatably mounted on the shaft 42 The collar 8'7 thus ties all of the arms '70 together for equal movement about their respective pivot pins '71. A coil spring 88 encircling theshaft 42 between the cup 59 and the collar 8'7 is maintained underconstant compression between the parts and not only constantly urges the collar 8'7 rearwardly, and thus the inner ends of the arm '70 rearwardly, but also constantly urges the cup 59 forwardly The force of the spring 88 is superior to any axial force that may be exerted by the spring 60 and consequently urges the complementary teeth of the sleeve 44 and cup' 59 'into complete engagement. I

An additional feature of the construction which is desirable in connection with the present inven-. tion, but which is to be understood as not being" essential in all cases, is a sleeve 90 rotatably and slidably mounted upon theshaft 42 rearwardly of the collar 87. The collar 90 carries at its forward end a thrust bearing indicated generally as at 91 and is peripherally grooved as at 92 to receive diametrically opposite pins 93 carried by the upper yoked end of a lever 94'fixed to a shaft 95 rotatably supported in the casing 24. Exteriorly of the casing 24 the shaft 95 is provided with a foot pedal 96 of conventional construction, as best illustrated in Fig. 1. -.It might also be noted before passing on to the explanation of the operation of the above described mechanism that .it

may be preferable to provide an oil throw ring such as 9'7, as illustrated in Fig. 3, on the tubular periphery of the sleeve 44 so as to direct lubricant away from the friction surfaces of the clutch, and

' also to provide the recessed rear face-of the flywheel 32 with an inclined wall such as 98 and cooperating drain openings 99 for the same purpose.

Considering now that the above described clutch mechanism is incorporated in a motor vehicle in the manner illustrated in Figs. 1 and 11 for the purpose of illustration, it will first be'supposed that the vehicle is at rest and the engine 18 is not operating. In such a case it will be obvious that the weights '72 will not be subjected to centrifugal force and consequently the force of the spring 88"wi1l be suflicient to force the collar 8'7 rearwardl'y, carrying with it the inner ends of the arms '70 and consequently releasing the clutch I drivenplate 46 from clamped relation between the pressure ring 65 and the rear face 36 of the fly wheel 32. In such a case, regardless of the shiftableposition of the transmission mechanism 25, the engine 18 is totally disconnected from the rear wheel 1'7 of the motor vehicle.

In case it is'desired to drive the motor vehicle, the first operation will be to start the engine 18. inoperation, and when this occurs the fly wheel 32 in rotating will, of course, subject the weights '72 on the ends of-the arms '70 to a centrifugal action tending to throw the weights radially out-' 'wardly. The force of the spring 88 is so proportioned relative to the mass and position weights '72 with respect to their pivotal points '71 that the engine may rotate at idling speed, nor

mally in the neighborhood of 350 revolutions per minute,-without the combined-foro of the centrifugal action of the various weights '72 overcoming the force of the spring 88 sufliciently to cause an engagement of the clutch. It will thus be ap: I

parent that-under any circumstance when the of the engine is rotating at or in the neighborhood-of As the speed of the engine is gradually increased above idling speed the centrifugal force actingon the various weights 72 increases, gradually overcoming the force of the spring 88 with' gradual increase of engine speed, and the arms '70 begin to swing aroundtheir pivot pins '71. This continues until the plungers '79 engage the pressure ring 6'7 and resiliently urge it forwardly for clamping relation with respect to the clutch driven plate 46. Due to the plungers 79 being resiliently'pressed outwardly'by the springs 82, and particularly if the speed of the engine is increased gradually, the clamping effect on the clutch driven plate 46 willbe gradually increased allowing a gradually decreasing amount of slippage between the disc 46 and the fly wheel until the disc 46 is eventually clamped against rotation the arms '70 be stopped from further pivotal movement by engagement of the Weights '72 by the stop pins '75 before solid contact occurs between the arms '70 and thepressure p1ate 65, the' springs 82, in such case, being designed to exert sufficient pressure to insure the clutch transmitting thefull torque without slippage. It may also be pointed out that in such a design the pins '75 maintain the weights '72 in a-flxed position relative to the axis of the clutch over the greater speed range-of the engine and thus maintain the balance of the clutch over the higher speed ranges of the engine.

With the clutch thus completely engaged the engine is speeded up to the desired pointand the driver then removes his foot from the accelerator.

'In such case the direction of the torque being I V transmitted through the propeller shaft 26 be'- tween the rear wheels and tlR engine will be reversed, it being understood that the clutch is still engaged, with the result that the tendency will be for the vehicle to drive the engine and toturn the clutch shaft 42 at a rate of speed greater than that of the crank shaft 30. en

this occurs the torque,in being transmitted from the shaft 42 to the clutch driven plate 46 through the cup member 59 and sleeve member 44, will necessarily have to be transmitted through the member 59 will rotate relative to the member 44 and in rotating,

.cam surfaces on the sure on the accelerato a substantially because of the cam surfaces, will be forced rearwardlyagalnst the force of the spring 88 which, because of the movement of the arms 70 in moving the clutch to fully engaged position, has been placed under an increased compression force.

Considering the force of reaction between the members 44 and 59 to be suflicient in the case under consideration, the member 59 iii-moving rearwardly will force the collar 87 rearwardly, 'moving'the inner ends of the arms '10 rearwardly and consequently moving the weights 72 inwardly against the centrifugal force to which they when this occurs'the driven disc 46 will be released from the fly wheel and the clutch will have been moved to disengaged position, permitting the transmission 25 to be shifted into the next gear and the operation repeated until the transmission is placed in direct or high speed position, after which the motor vehicle may be driven in the usual manner.

If, while the motor vehicle is being driven in direct or high gear, the operator releases his pres,

under which circumstances the vehicle will immediately attempt to drive the engine, the reaction between the cam surfaces on the members 44 and 59 will tend to move the clutch to disengaged position and, if

the operator has removed his foot entirely from the accelerator, as soon as the clutch is dis engaged in this manner the engine speed will immediately be reduced to its idling speed, allowing the spring 88 to move the weights 72 to their innermost positions in which case the clutch will automatically be disconnected without reference to the torque being transmitted to the clutch from the drive wheel of the. vehicle. When this happ s the torque being transmitted between the members 44 and 59 will immediately drop to negligible amount, permitting the torsion spring 60 to return the members 44 and 59 to their normal positions, and the motor vehicle will then continue to coast with the engine completely disengaged from the driving wheels.

ing wheels for any reason, all-that is necessary is for the operator to momentarily step on the accelerator so as to increase the engine speed sumciently to again. cause outwardly against the force of the spring 88 tothe driving wheel of the vehicle.

The amount of torque which must be transmitted through the propeller shaft when the rear,

The lead of the cam surfacesexerted through the are subjected. Obviously,

,the use of an engine to forwardly against the action Obviously, if the clutch is wheels are tending to drive the engine, in order that the member 59 will rotate relative to the member 44 sufiiciently to cause a disengagement of the clutch, may, of course, be varied in the construction indicated in a number of different ways. For instance, the lead of the cam surfaces of the members 44 and 59 may be varied to effect this feature, the center of mass'of the weights 72 with respect to the axes of the pins '71 and the amount of such masses may be varied to accomplish the same result, and, likewise, the force of the spring 88 and also the spring 60 may be varied with the same end in View.

It also may be noted thus be exerted to cause disengagement of the clutch when the vehicle wheels are driving the engine varies throughout the range of speed of the engine due to the variation in the centrifugal force acting on the weights 72 over the range of speed. However, this last feature does not efiect the desirable ,results obtainable with the construction described for the reason that the amount of torque which may be caused to be propeller shaft in driving the engine from the rear wheels will also vary with the speed of the vehicle and, consequently, these two factors offset each other.

that the force which must Consequently, with the construction above described the operation of the clutch is entirely automatic and may be controlled solely by the operator of the vehicle through proper use of the engine speed governing means. Furthermore,

the construction is such that, when desired,'by

proper manipulation of the' engine governing means which, of course, is normally the ace celerator pedal, theengine may be disconnected from the driving wheels at most periods of operation where the driving wheels tend todrive the engine although, as previously explained, by proper manipulation ofthe accelerator disengagement of the clutch zmay beprevented even ,when the engine is being driven by the driving wheels. I -It will,-however, be obvious that-in certain cases it may be desirable to use the engine to its fullest extent as a brake, such conditions arising, for instance, when a motor vehicle is traveling down a mountain side, and in order to insure its fullest extent as a brake under such conditions, additional means including the collar 90, lever 94, shaft 95 and pedal 96 may be provided.

When the pedal 96 is depressed it acts with the shaft 95 and arm 94 to move'the collar 90 forwardly-and the collar 90 in moving forwardly abuts, against the collar 8'7 and tends to move it of the spring-88. in its disengaged position, as illustrated in Fig. 3, and the upper end of the pedal 96 is moved forwardly causing the collar 87 to move forwardly, the arms 70 will be ,swung around their respective pivot pins 71 toward clutch engaged position and the clutch the'in'embers'44and59. Consequently, in any case where it is desired to temporarily'overcome the*automatic disengaging features of the clutch, a suitable amount of pressure applied to the pedal 96 will effectively provide the desired result.

Although previously mentioned, it is desired to call attention to the fact that the fingers 85 on the inner ends of the arms in being enequal and uniform movement of axis of the clutch and,

any condition of clutch unbalance which would tend to set up undesirable vibration due to any non-uniformity that might otherwise occur in' the movement of the masses E2.

The modified form of the invention shown in Figs. 6 to 10 inclusive is, ingeneral, substantially identical to that described in the previous views and. consequently, equivalent parts are indicated by the same numerals as in the first described construction except that suchmembers bear a prime mark. The main difference is that in the modified construction the cup member 59' in moving rearwardly under a reversal oi the usual direction of torque reactions in the propeller shaft to client a disengagement oi the clutch as previously explaineidoes not act through the fingers 85' of the arms to release the cluteh, but instead contacts directly with. an annular flange 100 rigidly carried by a web 101 secured to the pressure plate 65'. The cup member 59' in moving rearwardly as described and in contactingdirectly with the flange 100 consequently urges the pressure plate 65' rearwardly and the pressure plate in reacting against the arms '10 causes the arms, 70' to be rotated towards their inoperative positions.

In this construction, in order to eliminate as completely as possible any friction between the member 59' and the flange which might otherwise interfere with the free functioning of the member 59, and in order to eliminate as completely as possible any friction that might be apparent between the cam teeth of the members 44 and 59, anti-friction balls are provided at these surfaces. As indicated best in Figs. '1, 8

.and 9, the cam surfaces 102 of the member 59' are grooved as 103 on their forward face, and received in these grooves are hardened balls 104 which project beyond the corresponding faces 102. Preferably some means such as a retaining strip- 105 overlying the cam faces and provided with slots such as 106 through which the balls 104 may project, are secured to such faces by screws such as 107 or other suitable means.-

Likewise, the rear face of the member 59' which would normally directly contact with the forward face of the annular flange 100 carried by the pressure plate 85' is grooved as at 110, and balls 111 are received in such grooves and are retained therein by a suitable retainer member 112 of a type generally similar to the members .105 previously describedexcept that in this case the retainer members 112 allow continuous rotation 6! the balls 111.

From the foresoins description it will be apparent that by the .use'of the present invention an automatically. actuated clutch of the cen-v trifugally controlled type 1 Provided which. in

.additiontotheusualfeatures foundinthis'typc of clutch, embodies in addition and ass unit :gest itself to a variety oi may therewith means for automatically disengaging the clutch .at times which would be impossible with centrifugally controlled clutches ashereto- ,fore constructed.

It is also desired to repeat that. although in the description of the operation of the present clutch such description has, been limited entirely to its application to a motor vehicle, its construction and operation when once appreciated will sugwidely difierent applications and accordingly, solely toits application in a motor vehicle.

Furthermore, it will'be apparent that, although I haveillustrated buttwo embodiments oi the.

various other modifications present invention,

be readily effected by those skilled in the art when once my teachings are made imown to them'and, consequently, formal changes may he made in the specific embodiment oi the invention described without departing from the spirit or substance of the broad invention, the scope oil which is commensurate claims.

I claim:

1. in a centrifugal clutch, in combination, a. pair of rotatable elements, a pressure plate dis posed on that side of one oi said elements opposite to the other of said elements, a plurality or weighted arms pivotally secured one or said elements, and a resilient pl er carried by each of said arms and positioned to engagesaid pressureplate when said arms are movedunder the influence of centrifusal force.

a In a centrifugal clutch, in combination, a

pair of rotatable elements, a pressure plate moved under the influence of centrifugal force,

and means for adjusting the position ct said plungers with respect to their corresponding 3; In a centrifugal clutch, in combination, a pair of rotatable elements, a pressure plate dis posed on that side of one of said elements opposite to the other of said elements, a plurality or weighted arms pivotslly secured to one of said elements, resilient means carried by each of said arms and positioned to engage said pressure plate when said arms are moved, under the influence of centrifugal force, and relatively rotatable cam members one or which is constantly "rotatable with. one of said rotatable elements, said cam -membcrs being cooperable with each other to causeasial displacement of one relative to the .other upon relative rotational movement between them in one direction and one of said cam members cooperating with said pressure plate to cause simultaneous axial displacement against theurgeofsaidresilientmeans. K R

EWARD I. nrcmsou, J's.

said elements, a plurality of I do not limit myselif with the appended 

